97[247]BkBerkelium
Berkelium (Bk) — element 97actinide · period 7
Berkelium is a chemical element with the symbol Bk and atomic number 97. It is an actinide in period 7 of the periodic table (the f-block), with a standard atomic mass of [247] u. At room temperature (25 °C) berkelium is a solid.
💡 Known for: Named after Berkeley, California; it was used as a target to create element 117, tennessine.
# Berkelium properties
| Symbol | Bk |
|---|---|
| Atomic number | 97 |
| Atomic mass | [247] u |
| Category | actinide |
| Group | — (f-block, no group number) |
| Period | 7 |
| Block | f-block |
| Electron configuration | [Rn] 5f⁹ 7s² |
| Full configuration | 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f⁹ 6s² 6p⁶ 7s² |
| Electrons per shell | 2, 8, 18, 32, 27, 8, 2 |
| Protons / electrons | 97 / 97 |
| State at 25 °C | solid |
| Melting point | 1259 K (985.9 °C, 1806.5 °F) |
| Boiling point | 2900 K (2626.8 °C, 4760.3 °F) |
| Density | 14.79 g/cm³ |
| Electronegativity (Pauling) | 1.3 |
| First ionization energy | 6.198 eV |
| Atomic radius | 170 pm |
| Discovered | 1949 |
# Electron configuration of berkelium
The electron configuration of berkelium is [Rn] 5f⁹ 7s², written out in full as 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f⁹ 6s² 6p⁶ 7s². Its 97 electrons fill 7 shells as 2, 8, 18, 32, 27, 8, 2, so the outermost shell holds 2 electrons.
# Related elements
CmCuriumprevious elementCfCaliforniumnext elementAcActiniumactinideThThoriumactinidePaProtactiniumactinideUUraniumactinideNpNeptuniumactinidePuPlutoniumactinideAmAmericiumactinideEsEinsteiniumactinide
# Berkelium FAQ
What is the atomic number of berkelium?
The atomic number of berkelium is 97: every berkelium atom has 97 protons in its nucleus. Its symbol is Bk.
What is the atomic mass of berkelium?
The standard atomic mass of berkelium is [247] u (the mass number of its longest-lived isotope, since it has no stable isotopes).
What is the electron configuration of berkelium?
Berkelium's electron configuration is [Rn] 5f⁹ 7s² (1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 5f⁹ 6s² 6p⁶ 7s²), with 2, 8, 18, 32, 27, 8, 2 electrons per shell.
Is berkelium a metal?
Yes. Berkelium is an actinide, one of the metals.
What is the melting point of berkelium?
Berkelium melts at 1259 K (985.9 °C, 1806.5 °F) and boils at 2900 K (2626.8 °C, 4760.3 °F).
What is berkelium used for / known for?
Named after Berkeley, California; it was used as a target to create element 117, tennessine.